ComorbidityRetrospective StudiesRisk FactorsUnited StatesMental DisordersTreatment OutcomeAge FactorsPrevalenceCohort StudiesSeverity of Illness IndexAnxiety DisordersDiagnostic and Statistical Manual of Mental DisordersRisk AdjustmentMood DisordersLogistic ModelsProspective StudiesRisk AssessmentChronic DiseaseFollow-Up StudiesHospitalizationTime FactorsCross-Sectional StudiesMedicareDiagnosis, Dual (Psychiatry)Quality of LifeProportional Hazards ModelsMultivariate AnalysisDepressive DisorderSubstance-Related DisordersHospital MortalityRegistriesPsychiatric Status Rating ScalesDepressionDiabetes Mellitus